1. Field of the Invention
The present invention relates in general to automotive door lock assemblies and more particularly to the automotive door lock assemblies of a thief-proof type.
2. Description of the Prior Art
In known automotive door lock assemblies hitherto used, there is a type which comprises a key cylinder which is mounted on the door to face the outside of the same, a lock/unlock mechanism which can switch between a lock condition wherein manipulation of both outside and inside handles of the door for opening the door is inoperative and an unlock condition wherein the manipulation of them is operative and an override mechanism which can make the manipulation of the inside handle operative even when the lock/unlock mechanism is in the lock condition.
However, due to its inherent construction, the door lock assemblies of this type have failed to exhibit a satisfied thief-proof function. That is, even when the door is locked with the lock/unlock mechanism kept in the lock condition, manipulation of the inside handle by a picking tool or the like inserting through a small clearance for example between a door window pane and the door body would induce switching of the lock/unlock mechanism to the unlock condition thereby causing illegal opening of the door.
One of the automotive door lock assemblies that overcomes the above-mentioned drawback is disclosed in Japanese Patent First Provisional Publication 4-20684. That is, in the door lock assembly of this publication, there are further employed a safety mechanism which can make the override mechanism inoperative in a certain condition and an electric actuator which actuates the safety mechanism with an electric power. That is, by operating the safety mechanism by the electric actuator, the manipulation of the inside handle becomes inoperative in the certain condition.
However, even the door lock assembly of this publication has failed to provide users with a satisfaction. That is, in this door lock assembly, the two electric motors for respectively actuating the safety mechanism and the lock/unlock mechanism are separately arranged in the assembly, and thus the entire construction of the door lock assembly is bulky.
It is therefore an object of the present invention to provide a thief-proof automotive door lock assembly which is simple in construction and compact in size.
According to the present invention, there is provided a thief-proof automotive door lock assembly which generally comprises a door lock which includes first and second lock/unlock mechanisms and an electric actuator which includes first and second electric motors and first and second operation levers, wherein the first and second lock/unlock mechanisms can be brought to respective lock conditions for providing a so-called xe2x80x9csuper-lock conditionxe2x80x9d thereby to improve the thief-proof function of the door lock assembly.
According to the present invention, there is provided an automotive door lock assembly for use with an automotive door having outside and inside handles mounted thereon. The assembly comprises a door lock including a first lock/unlock mechanism which switches between an unlock condition wherein manipulation of the outside handle is made operative and a lock condition wherein manipulation of the outside handle is made inoperative and a second lock/unlock mechanism which switches between an unlock condition wherein manipulation of the inside handle is made operative and a lock condition wherein manipulation of the inside handle is made inoperative; and an electric actuator mounted to the door lock for actuating the same. The electric actuator includes a housing secured to a base member of the door lock; first and second electric motors installed in the housing; a first operation lever straightly movably held by the housing, the first operation lever being actuated by the first electric motor to switch between an unlock position to cause the first lock/unlock mechanism to assume the unlock condition and a lock position to cause the first lock/unlock mechanism to assume the lock condition; and a second operation lever pivotally held by the housing, the second operation lever being actuated by the second electric motor to switch between an unlock position to cause the second lock/unlock mechanism to assume the unlock condition and a lock position to cause the second lock/unlock mechanism to assume the lock condition.